The Connection Between Sleep Apnea and Stroke

Obstructive sleep apnea (OSA) affects 20% of U.S. adults, of whom about 90% are undiagnosed. The major risk factors for OSA include obesity, male sex and a family history of OSA. There is a large body of literature showing that OSA is an independent risk factor for hypertension, heart disease, type 2 diabetes and stroke.  This case illustrates how a patient presented for elective admission for surgery and suffered a stroke.  

A 55-year-old man with obesity presented for elective surgery for a chronic nonhealing ankle fracture. The patient reported a long history of loud snoring and type 2 diabetes. He was administered a general anesthetic and had no issues during the case. The patient recovered and was admitted to the hospital overnight, and it was noted that he had marked bouts of hypertension overnight while sleeping; the patient had no past history of hypertension. The staff also noted evidence of sleep apnea patterns of sleep and snoring. The patient was then discharged home. Three weeks later, the patient presented with a large embolic stroke and was admitted to the neuro-ICU. He was discharged to a rehabilitation facility with marked cognitive issues.  

This case illustrates how important it is for anesthesia providers to screen patients for OSA and educate patients about the major risks of OSA. There were also some key incidents during this admission that support the need for staff education. The episodes of hypertension during sleep and not while awake are a key sign of the cyclic sympathetic outflow that occurs during OSA. This also supports cyclic release of mediators that occurs during severe OSA that can affect the endothelium and cause activation of coagulation cascade. The snoring can also cause direct vibratory trauma to the carotid blood vessels, and also cause endothelium damage on the interior of those vessels that can generate a clot.  

We as anesthesia providers should be at the forefront of identification of OSA and have a protocol to educate patients and refer them to sleep specialists for testing and proper treatment. This can be a major public health contribution of our specialty.